Cleft palate is one of the most frequently occurring birth defects. The goal of cleft palate surgery is to provide adequate velopharyngeal (VP) function to enable normal speech development. Although most infants undergo surgery by 9 to 12 months of age, definitive assessment of VP function is not possible until the child is a) at least 3 years of age, b) uses multiple word utterances, and c) is fairly cooperative for clinical procedures. Currently, it is known that at least 25% of children will require secondary palatal surgery to correct persisting VP dysfunction. In addition, the majority of children (approximately 70%) will require behavioral speech therapy to address various communication issues related to clefting. The long term objective of this proposal is to explore the use of a novel, non-invasive assessment procedure to determine adequacy of VP function in infants soon after cleft palate surgery. 48 infants with non-syndromic cleft palate with or without cleft lip will be studied longitudinally at four time points beginning at approximately 12 months of age: pre-surgery, 2 weeks post, 4 months post, and 12 months post surgery. 12 infants without cleft palate also will be studied longitudinally at three corresponding time points: 12, 16, and 24 months of age. A double-barreled nasal cannula and microphone will be used to record nasal ram pressure and vocalizations of the infants, respectively. Vocalizations will be coded as cries, isolated vowels, single consonant-vowel syllables, and multiple syllable utterances and classified relative to VP status as closed, partially closed, or open based upon nasal pressure data. At 24 months of age, the children with cleft palate will be audio recorded and a panel of listeners who are blind to the nasal pressure assessments will perceptually evaluate VP closure of the children. Specific aims include determining 1) the time course of VP closure in both groups of children, and 2) the sensitivity and specificity of the nasal pressure classifications of VP status as compared to perceptual speech assessments of children with repaired cleft palate at 24 months of age. We anticipate that the results of the study will a) generate much needed physiologic information on the time course of VP closure during early speech development, b) provide early feedback to surgeons regarding the success of surgical techniques, and c) suggest behavioral and/or secondary surgical intervention strategies for children with VP dysfunction at earlier time periods than currently practiced. [unreadable] [unreadable] [unreadable]